A 71-Year-Old Man with Gastric Cancer

January 15, 2021
Daniel Catenacci, MD

Daniel Catenacci, MD, reviews the case of a 71-year-old man with gastric cancer.


Case: A 71-Year-Old Man With HER2+ Gastric Cancer

Initial Presentation

  • A 71-year-old man complained of a 3-month history of abdominal pain and bloating, a sensation of fullness
  • PMH: HTN, medically controlled; colonoscopy at age 53 was unremarkable; no family history of cancer
  • PE: patient appeared tired, abdominal distention; otherwise unremarkable

Clinical Workup

  • Labs: Hb 9.7 g/dL, plt 111 x 109/L; other lab values WNL
  • Upper endoscopy with biopsy: showed an ulcerative lesion 5.8 cm mass in the cardia of the stomach; biopsy confirmed gastric adenocarcinoma
  • CT of chest/abdomen/pelvis confirmed a 5.8 cm lesion with indistinct margins in the cardia of the stomach; 2 suspicious hepatic lesions
  • EUS: gastric cancer lesion confirmed invasion of the muscularis propria
  • Mutational testing: MSI high, PD-L1 0%, HER2 3+ by IHC
  • Stage IV gastric adenocarcinoma; ECOG 2

Treatment

  • He was started on XELOX/CAPOX + trastuzumab
    • Dose reduced due to grade 2 diarrhea; unable to control after 4 cycles; discontinued treatment
  • Treatment initiated with a pembrolizumab
    • After 24-months of treatment without progression of disease pembrolizumab was discontinued
  • The patient was started on trastuzumab deruxtecan; repeat HER2 expression testing was not indicated